On Thu, 20 Dec 2018, Sven Schreiber wrote: > Hi, > > I'll admit right away that this question has no real practical problem > behind it, it's just out of internal consistency: > > The mean() function accepts a list and then averages across the > members of the list (and returns a series of per-obs-averages). > > In contrast, the pmean() function doesn't have this second use, it > only accepts one series (as does mean). Any particular reason why not? > > The same goes for pmax(), pmin(), psd(), psum(), and perhaps also > pxsum(), I guess. Well, this makes sense I suppose, snce pmean() and friends are supposed to operate "vertically", so to speak, through time, so I can't really imagine what you might want to have with a list argument. Perhaps pmean(mean(X))?